Folding layout: 3/8" or 3/4" plywood?

3/4" is also going to be heavy. Framed 3/8" should be good in my opinion.

Any reason why 1/2” couldn’t be an option?

Gene

@Genemed posted:

Any reason why 1/2” couldn’t be an option?

Gene

I listed 3/8 and 3/4 because both were shown in the diagram provided in the article. It should only have listed one or the other consistently, but they made a mistak and I assume 3/4 was a typo.  If so, I would go with the 3/8 shown.

I have a vague memory of the article.  I'm not that old but bought a couple of boxes of old MR's.  I don't have them any more but these issues are now available on CDs and online.  Most likely they ripped the 3/4" plywood down to 3" width to frame the two halves.  One 4' end piece of framing would be 6" to 8" wide with the wheels mounted on the outside,  A piano hinge would join the two 4' by 4' pieces together.  The legs would be removable or fold up into the bottom side.

Jan

This is not a direct answer/opinion to your question however if you have concerns about ease of storage/weight and or the amount of space needed to store; while considerably more expensive you may want to consider using four 2'X4'X36" or one 4'X8'X36" Bora Centipede work benches as your base.  I have used them to good affect.  Easy to handle, comparatively light weight, and virtually no storage space compared to dimensional lumber.

Just another option.

Personally, I think that 3/8 is way too thin.  Go with 1/2 BC grade sanded plywood.  The additional weight will be nominal.  Do not let the sun get on it, or it will start warp in just an hour or two!

If you go with 3/8, then I would strongly suggest that you use industrial grade adhesive to glue it down flat on the framework, before you build the legs.  PL3x adhesive is available at Home Depot and Lowes.   (Keep the windows open when you put the adhesive down!)    Before you squirt the adhesive out, quickly vacuum the underside of the plywood, and the top edge of the framework, to remove dust and surface stuff.     

Once you apply the adhesive to the plywood, very carefully set the plywood on the framework (both the rim lumber and cross supports) and shift it around immediately to get it perfectly aligned.  After you do this, very carefully add weigh to top of the plywood where needed, so that it is totally flat.  (I use tool boxes.)

Let it dry for a full 24 hours, in a dry area, out of the sun, and should not need to screw it down.    Same goes for using 1/2 plywood.

Mannyrock

@Former Member posted:

... you may want to consider using four 2'X4'X36" or one 4'X8'X36" Bora Centipede work benches as your base.  I have used them to good affect.  Easy to handle, comparatively light weight, and virtually no storage space compared to dimensional lumber.

Chuck,

Good alternative, and they'd be even better if they were only 8" tall.  (If I recall the layout that the OP is speaking of was only a few inches off the ground, but I may be wrong about that.  Anybody recall?)

Mike

Maybe overthinking/overbuilding?

I built a [very] lightweight 4X8 "portable" layout that worked quite well. 1X2 framing using Oak for the two long pieces and pine for the cross-pieces. ¼ inch "floor underlayment" plywood deck (that stuff is hard-surfaced, stiff and dimensionally quite stable). It rested on the black drawer set seen in the first pic when in use and when we had guests I simply picked it up and carried it from the living room to the basement (hence portable).

Thank you all

if you use construction adhesive (liquid nail &or similar) and staples/screws to secure the panel to your frame you can use 1/4" thick material and it should be very adequate for a moving/temporary setup. purchase a good quality plywood, and anything thicker than 3/8" will just be adding weight.

Ben,

Here's a link to the NMRA index.  Try searching on "folding".  The February 1942 Issue 2 of Model Builder shows an article "Apartment Layout".

http://www.olimpia.com:8084/search

Jan

Thanks! I have a plan which I want to use (which I can't post here because that would violate copyright laws). I will try 1/2" plywood and split the difference between the two conflicting dimensions shown in the plans.

For a portable layout, I'm with Ben, 1/4" plywood and just make sure you have sufficient support between spans.

The top surface is prevents the table frame racking.  You don't need anything like 1/2" plywood.

If you have cross members every foot you can use homasote (if you can find it) in lieu of the plywood, and have a surface that is easy to fasten track to and is sound absorbing.  My very first layout was 8' by 5' topped only with 1/2" homasote and cross members every 16".  Twenty years later it was still flat as when new.

You could use lauan plywood which is lighter (about 1/8" thick) and top it with homasote or other material.

Jan

@BenLMaggi posted:

Thanks! I have a plan which I want to use (which I can't post here because that would violate copyright laws). I will try 1/2" plywood and split the difference between the two conflicting dimensions shown in the plans.

Hi Ben, I am curious about the plan, can you post the date of the magazine, Can I assume it was in Model Railroader?  I have a cousin that wants a portable layout and wonder if this would be appropriate for him. 

Keep us posted on your progress. Best, Dave

OK,  I found the plan in Toy & Model Trains from the editors of Model Railroader, published in 1986.  The frame that flips over, does not have any cross bracing that would keep the plywood from warping.  So, you may want to consider using the 3/8 inch or 1/2 inch plywood.  That layout, while on wheels, does not look very portable and looks to be very heavy, with the 2x4 side frames, legs, etc.  Maybe its just me, but it did not look that easy to lift up and over. The wheels would need to be locked in place to do that lift.

The Magazine had another portable layout using two foam core boards, that would be very light and could be supported or use the concept that Lew geysergazer   shows with his layout. 

Hope this helps and good luck.

Dave

That is the article I am referencing. It only has to roll a couple of feet under my own train layout when not in use. Thanks.

Hi Ben,  I am sure you will be able to improve upon the design,  its an interesting concept.  I also note that in the November/December 2023 issue of CTT, they have a layout project that used 3/4 inch plywood.   I guess they don't read all of the posts here about 1/4 inch plywood.  I have a piece of 1/4 inch plywood that my dad used to make a race car layout for me in 1962.  Its really held up well. 

I don't get trying to make a small portable layout weigh a ton, I'd use the lightest stuff that will work.

If you want to make sure that plywood doesn't warp, then consider adding at least a few 2x3 (not 2x4) cross supports.  They are really really light if you use the cheap spf  (white wood at Lowes).    Even a support every 24 inches would greatly help. Be sure to glue them to the underside of the plywood as you nail them in.

And, after your plywood is on the final framework, then totally seal the plywood, top and underside, and the cross supports and surrounding outer framework, with a coat of Kilz 2 primer.  This will prevent it from absorbing moisture, to prevent warping.

Light framework by itself can warp pretty badly, even inside a house, unless you have a great humidity control in your house which keeps the humidity pretty constant all year round.  One coat of Kilz 2 is pretty cheap insurance! 

Mannyrock